Within the research field of HCI task models are widely used for model-based development of interactive systems. Recently introduced approaches applied task models further to model cooperative behaviour of people interacting in smart environments. However there is a lack of usability methods to support the needs of evaluations during a model-based development process for smart environments. Particularly during early stages of development building a prototypical environment for user evaluations is resource consuming. To overcome the challenges we present a process model and according tool support. We provide the virtual smart environment ViSE to conduct expert evaluations and user studies during a user-centred design process, supporting iterative evaluations.